Industrial furnace and oven wall



Jan. 16, 1968 w. c. SHIRLEY ETAL I. 3,363,889I

INDUSTRIAL FUNACE AND OVEN WALL Filed July El, 1966 I y /5 ,L+ ALV-2 E v /NvE/v roRs. H E l w/L/AM c. sH/RLEY and 1 CHESTER c. CARTER A l Ivor/lays United States Patent C) 3,363,889 INDUSTRIAL FURNACE AND @VEN WALL William Clark Shirley, Mount Lebanon, and Chester 'Charles Carter, Pittsburgh, Pa., assignors to Loftus Engineering Corp.

Filed .l'uly 21, 1966, Ser. No. 567,004

3 Claims. (Cl. 26S- 40) The present invention relates to improvements in industrial furnace and oven wall construction, employing high velocity heating air moving therethrough whereby heat losses through the metal and insulating refractory walls thereof are substantially reduced, resulting in an increase of eiiiciency and a reduction in cost of heating.

Such furnaces and ovens normally comprise an outer metal shell, an inner metal shell disposed in spaced relation to the outer shell and suitable, usually block type, insulation between the inner and outer metal shells. The inner metal shell is usually comprised of heat resistant metal and the heating of the metals disposed within the furnaces and between said inner shells is usually accomplished by re-cycling or passing heated air at substantially high velocities over and around the metals to.be heated. Thus the necessity to avoid heat losses through the insulation.

One object of the invention is to provide means to retard heat transfer from the inner heating chamber through the insulation about the inner heating chamber by suitable insulative barriers. Other objects will be made apparent from the following description.

Referring now to the drawing:

FIG. l is a typical elevation of a portion of the inner face of the furance or oven heating chamber embodying the invention;

FIG. 2 shows a section taken on lines II-II of FIG. 1 comprising a typical cross section through the inner and outer metal furnace walls of the invention and the insulation therebetween; and

FIG. 3 shows a typical vertical section taken on lines III-III of FIG. 1.

Referring now in detail to the drawings, reference character 1 indicates a typical metal outer furnace wall and 2 indicates heat resistant metal panels forming the inner face of the furnace heating chamber. Preferably the panels 2 have suitable diagonal breaks 3 upon the exposed face thereof for stilfening the panel. Preformed block insulation 4 if rst installed against the inner face of outer wall 1 for substantially the height thereof, for purposes of illustration and not limitation, insulation 4 may be of 24 x 48" x 4 thick 700 F. block insulation disposed in longitudinal rows with the blocks in each row in abutting relation to cover the vertical face of wall 1 and are preferably attached thereto by suitable adhesive. Upon the inner face of insulation 4 is applied a continuous aid and heat barrier of aluminum foil 5 of suitable thickness, for example .0075 minimum, and preferably annealed. The aluminum foil 5 is preferably bonded to the insulation blocks 4 by a suitable adhesive, such as sodium silicate of Baum 38.

The aluminum or other suitable metal foil 5, to be effective should cover the face of each section 4 of block insulation and the joints between said insulating blocks. Preferably the abutting joints of insulation 4 in one longitudinal row is staggered in relation corresponding abutting joints in adjacent longitudinal rows. Hence not only the face of each insulation block but the joints between them should be covered by the foil 5.

To assemble the inner side wall metal sheets 2, with the insulation 4 and the outer metal wall 1, suitably spaced openings 6 are iirst drilled through the foil 5 and block insulation 4 to receive studs 7 which are of a length to protrude through the plane of the sheets 2. Thereafter ICC the studs 7 are inserted through said openings `6 and secured at one end to wall 1 as at 8. Preferably this is done by welding, as is well known in the art. As best shown in FIGS. 1 and 2 of the drawing, the said sheets 2 are assembled frm the base 9 (FIG. l) of the inside Wall upwardly. To effect this assembly, each vertically disposed sheet 2 has block insulation 10, such as 1400 F. block insulation, filling the space between the upper and lower anges 11 and 12 of the sheet. Preferably the block insulation 10 is of greater thickness than the width of flanges 11 and 12 of sheets 2 as shown in FIG. 2 and projects therefrom for engagement with foil barrier 5. With two adjacent sheets 2 disposed upon opposite sides of each stud 7, a keeper 13 is applied over the stud and block insulation 14 which may be of material similar to 10, is inserted between opposite sides of the stud and the adjacent keeper arms (FIG. 2). As best shown in FIGS. 1 and 2, keeper 13 is of generally channel shape having a web portion 13a of substantially the vertical length of panel 2 and rearwardly extending side flanges 13b which preferably terminate short of foil barrier 5. The width of keeper web 13a is preferably less than the spacing between adjacent edges of panels 7. Thereafter a lapping strip 15 (FIG. l) is applied over the keeper 13 and adjacent faces of panels 2 and a washer 16 and nut 17 is applied to each stud 7 fastening the sheets 2, keepers 13 and insulation blocks 10 and 14 in preferably abutting relation with aluminum barrier 5. Preferably an insulation 18, such as the commercially available product Fiber-Fraai is packed around the stud 7 (FIG. 2) as insulation and filling the space between blocks 14 and opening 6 in insulation 4.

From the foregoing description, it will be apparent that we have provided an eilicient heat barrier or insulation between the outer face 1 of the furnace wall and the inner wall plates 2. Any porosity in insulation 4 is overcome by the aluminum heat barrier 5 and the high temperature insulation 10 and 14 retards passage of heat from the inner chamber through the outer wall 1. The insulation 18 about stud 7 prevents free passage of heat through opening 6 in the insulation 4.

By reason of the heating of such furnaces being provided by hot gases moving through the chamber dened by the spaced panel side walls 2 in substantia1 volume and at substantial pressure, the construction herein disclosed provides greater economy and eiiicie-ncy than obtainable from prior art constructions. The spacing between keeper portions 13b and the adjacent wall plates 2 for expansion of the latter. Such spacing does not cause heat loss through the outer wall by reason of the insulating foil barrier 5.

We claim:

1. l-n an industrial heating furnace for preheating and annealing metal for further processing, in combination a suitably reinforced plate -metal outer wall having a substantially planar inner face,

block insulation disposed in abutting relation over the said wall planar inner face and adhesively attached thereto,

a non-porous foil applied over the entire exposed face of said block insulation and bonded thereto,

a plurality of longitudinal and vertically spaced apertures through said foil covered block insulation and terminating at the inner face of said metal outer wall,

metal stud members disposed within said apertures and secured to said outer wall plate and extending therefrom for support and attachment of inner wall plates,

vertically disposed rows of inner wall plates spaced longitudinally of said outer wall plate and provided with top and bottom longitudinal flanges extending towards said outer wall and high temperature block insulation of a thickness greater than the Width of said anges filling the space therebetween, and

insulated means mounted on each said studs and embracing the adjacent inner Wall plates for retaining the latter and the insulation thereon in abutting relation with the said block insulation adhesively attached to said outer Wall plates.

2. The combination as detined in claim 1 wherein said insulated means comprises a retainer plate overlapping adjacent spaced faces of said inner Wall plates, a U-shaped member disposed between said inner Wall plates in spaced relation thereto and to said stud and block insulation at opposite sides of said stud extending longitudinally of the adjacent Wall plates and in abutting engagement With said foil.

3. The combination as defined in claim 2, wherein the said stud is enclosed packed librous insulation for the d length thereof between the inner face of said outer Wall plate and said retainer plate.

References Cited UNITED STATES PATENTS 711,026 10/1902 Updike 110--1 2,377,528 6/1945 Spencer 110-1 3,138,899 6/1964 Hadley 52-410 XR 3,197,185 7/1965 Beattie 263-40 3,212,861 10/1965 Whitesides 110-1 CHARLES I. MYI-IRE, Primary Examiner.

J. I. CAMBY, Assistant Examiner. 

1. IN AN INDUSTRIAL HEATING FURNACE FOR PREHEATING AND ANNEALING METAL FOR FURTHER PROCESSING, IN COMBINATION A SUITABLY REINFORCED PLATE METAL OUTER WALL HAVING A SUBSTANTIALLY PLANAR INNER FACE, BLOCK INSULATION DISPOSED ABUTTING RELATION OVER THE SAID WALL PLANAR INNER FACE AND ADHESIVELY ATTACHED THERETO, A NON-POROUS FOIL APPLIED OVER THE ENTIRE EXPOSED FACE OF SAID BLOCK INSULATION AND BONDED THERETO, A PLURALITY OF LONGITUDINAL AND VERTICALLY SPACED APERTURES THROUGH SAID FOIL COVERED BLOCK INSULATION AND TERMINATING AT THE INNER FACE OF SAID METAL OUTER WALL, METAL STUD MEMBERS DISPOSED WITHIN SAID APERTURES AND SECURED TO SAID OUTER WALL PLATE AND EXTENDING THEREFROM FOR SUPPORT AND ATTACHMENT OF INNER WALL PLATES, 